Electrochromic display device and electrodeposition display device

ABSTRACT

Between each transparent pixel electrode driven by TFT as a drive device and a common electrode, a polymer layer located in contact with the transparent pixel electrode and electrically active to change in color by electrochemical oxidization or reduction and a polymeric solid electrolytic layer located in contact with the polymer layer and containing a coloring agent are interposed. since electrochemical oxidization or reduction brings about a color change, the contrast and the black concentration can be enhanced, and bronzing after long-time use does not occur.

TECHNICAL FIELD

[0001] This invention relates to an electrochromic display device and anelectrodeposition-type display device using a material variable in colorby electrochemical oxidation and reduction as the display material, andalso relates to a display apparatus using them.

BACKGROUND ART

[0002] Along with recent dissemination of networks, documents havingheretofore distributed in form of printed matters have come to bedistributed in form of so-called electronic documents. Additionally,more and more books and magazines are also becoming delivered in form ofso-called electronic publications.

[0003] Conventional way of accessing to these kinds of information is toread from CRT or liquid crystal displays of computers. However, it ispointed out that emission-type displays cause much fatigue due toergonomic reasons, and users cannot withstand long-time reading.Additionally, there is the disadvantage that a user can read it only atthe place where a computer is set.

[0004] Together with recent distribution of note-type computers, thereare devices usable as portable displays. However, also these devicescannot be used for reading over several hours or more because of theproblem of power consumption in addition to the reason that the displayis of an emission type. Reflection-type liquid crystal displays havealso been developed recently, and it will be possible to drive them withlow power. However, reflectance of liquid crystal under no display(black-and-white display) is 30%, and visibility of such displays ismuch worse than prints on paper. Therefore, users are liable to fatigueand cannot withstand long-time reading.

[0005] To deal with these problems, devices called paper-like displaysor electronic paper are under development. They color theirrepresentations mainly by moving color particles between electrodes byelectrophoresis or by rotating dichromatic particles in an electricfield. These methods, however, involve the problems that gaps amongparticles absorb light and thereby degrade the contrast, and a writingspeed acceptable for practical use (within one second) cannot beattained unless raising the drive voltage to 100 V or more.

[0006] Electrochromic display apparatuses (ECD) generating color byelectrochemical operations are superior to the electrophoretic schemesfrom the viewpoint of high contrast, and have already been used inpractical light control glass and watch or clock displays. However,since light control glass and clock or watch displays do not originallyneed the matrix drive, they are not applicable to the use of displaysuch as electronic paper. Additionally, quality level of black is bad,in general, and their reflectance is still low.

[0007] Displays such as electronic paper are inevitably exposedcontinuously to light such as sunlight or room light because of theirpurposes of use. In electrochromic display apparatuses of the typepractically used as light control glass and clock displays, certainorganic materials are used for forming black portions. Generally,however, organic materials exhibits poor light resistance, and arebronzed and degraded in black optical density after long use.Additionally, a matrix-driven display apparatus taught by JapanesePatent Publication No. hei 4-73764 is also known. However, the drivedevice merely composes a part of the liquid crystal display apparatus.

[0008] In view of these technical problems, it is an object of theinvention to provide an electrochromic display device and anelectrochromic display apparatus operative by matrix driving and capableof enhancing the contrast and the black optical density.

[0009] A further object of the invention is to provide an electrochromicdisplay device and an electrochromic display apparatus capable ofmaintaining the black optical density high without the problem ofbronzing even after long-time use.

DISCLOSURE OF INVENTION

[0010] To overcome the above-discussed problems, an electrochromicdisplay device according to the invention comprises: a first transparentelectrode controlled by a drive device: a polymer material layer locatedin contact with the transparent electrode and electrically active to bechangeable in color by electrochemical oxidation or reduction; apolymeric solid electrolytic layer located in contact with the polymermaterial layer and containing a coloring agent; and a second electrodelocated to interpose the polymer material layer and the polymeric solidelectrolytic layer between the first transparent electrode and thesecond electrode.

[0011] In the electrochromic display device having the above-summarizedconfiguration, when electricity is supplied between the firsttransparent electrode and the second electrode, the polymeric materiallayer interposed between the first transparent electrode and the secondelectrode is electrically activated to change in color. Since thepolymeric solid electrolytic layer adjacent to the polymeric materiallayer contains a coloring agent, the contrast upon a change in color inthe polymeric material layer can be enhanced. Since the firsttransparent electrode is controlled by the drive device, matrix drive ispossible when a plurality of drive devices are arranged.

[0012] An electrodeposition type display device according to theinvention comprises: a first transparent electrode controlled by a drivedevice; a polymeric solid electrolytic layer containing a coloring agentand metal ions; and a second electrode located to interpose thepolymeric solid electrolytic layer between the first transparentelectrode and the second electrode.

[0013] In the electrodeposition type display device having theabove-summarized configuration, when electricity is supplied between thefirst transparent electrode and the second electrode, electrochemicaldeposition by gold ions contained in the polymeric solid electrolyticlayer occurs in the polymeric solid electrolytic layer, and a change incolor occurs. Since the polymeric solid electrolytic layer contains acoloring agent, the contrast upon a change in color in the polymericmaterial layer can be enhanced, and matrix drive is possible by usingthe drive device.

[0014] When a plurality of electrochromic display elements each havingthe structure of the electrochromic display device according to theinvention or a plurality of electrodeposition type display elements eachhaving the structure of electrodeposition type display device accordingto the invention are arranged in form of a sheet, an electrochromicdisplay apparatus or electrodeposition type display apparatus is formed.

[0015] A method of manufacturing an electrochromic display apparatus oran electrodeposition type display apparatus according to the inventioncomprises: the step of forming transparent pixel electrodes and drivedevices on a transparent support structure; the step of forming apolymer material layer electrically active and changeable in color byelectrochemical oxidization or reduction, and a polymeric solidelectrolytic layer containing a coloring agent on the transparentsupport structure having formed the transparent pixel electrodes and thedrive devices, or the step of forming a polymeric solid electrolyticlayer containing metal ions and a coloring agent; and the step offorming a common electrode opposed to the transparent pixel electrodes.

[0016] Following to the above-summarized manufacturing method, it ispossible to manufacture the electrochromic display apparatus orelectrodeposition type display apparatus including a plurality ofelectrodeposition type display elements each having the structure ofelectrodeposition type display device or a pluralityof-electrodeposition type display elements each having the structure ofelectrodeposition type display device that are arranged in form of asheet.

BRIEF DESCRIPTION OF DRAWINGS

[0017]FIG. 1 shows fragmentary, perspective views of an electrochromicdisplay apparatus according to the first embodiment of the invention;

[0018]FIG. 2 is a cross-sectional view of the electrochromic displayapparatus according to the first embodiment of the invention;

[0019]FIG. 3 shows fragmentary, perspective views of anelectrodeposition type display apparatus according to the secondembodiment of the invention;

[0020]FIG. 4 shows cross-sectional views of the electrodeposition typedisplay apparatus according to the second embodiment of the invention;

[0021]FIGS. 5A, 5B and 5C are cross-sectional views showing respectivesteps of a manufacturing method of an electrochromic display apparatusaccording to the third embodiment of the invention, in which FIG. 5A isa cross-sectional view after progress up to the step of forming TFT andtransparent pixel electrodes, FIG. 5B is a cross-sectional view afterprogress up to the step of immersion into an electrodeposition vessel,and FIG. 5C is a cross-sectional view after progress up to the step offorming a polymeric solid electrolytic layer;

[0022]FIGS. 6A, 6B and 6C are cross-sectional views showing respectivesteps continuous from the steps of FIGS. 5A, 5B and 5C of themanufacturing method of an electrochromic display apparatus according tothe third embodiment of the invention, in which FIG. 6A is across-sectional view after progress up to the step of press-fitting asupport structure, FIG. 6B is a cross-sectional view after progress upto the step of bonding, and FIG. 6C is a cross-sectional view afterprogress up to the step of attaching a sealing material;

[0023]FIGS. 7A, 7B and 7C are cross-sectional views showing respectivesteps of a manufacturing method of an electrochromic display apparatusaccording to the fourth embodiment of the invention, in which FIG. 7A isa cross-sectional view after progress up to the step of forming TFT andtransparent pixel electrodes, FIG. 7B is a cross-sectional view afterprogress up to the step of forming a polymeric solid electrolytic layer,and FIG. 7C is a cross-sectional view after progress up to the step ofimmersion into an electrodeposition vessel;

[0024]FIGS. 8A, 8B and 8C are cross-sectional views showing respectivesteps of a manufacturing method of an electrodeposition type displayapparatus according to the fifth embodiment of the invention, in whichFIG. 8A is a cross-sectional view after progress up to the step offorming TFT and transparent pixel electrodes, FIG. 8B is across-sectional view after progress up to the step of forming apolymeric solid electrolytic layer, and FIG. 8C is a cross-sectionalview after progress up to the step of press-fitting a support structure;

[0025]FIGS. 9A and 9B are cross-sectional views showing respective stepscontinuous from the steps of FIGS. 8A, 8B and 8C of the manufacturingmethod of an electrodeposition type display apparatus according to thefifth embodiment of the invention, in which FIG. 9A is a cross-sectionalview after progress up to the bonding step, and FIG. 9B is across-sectional view after progress up to the step of attaching asealing material;

[0026]FIG. 10 is a plan view of the structure of one surface of anelectrochromic display apparatus or electrodeposition type displayapparatus according to the sixth embodiment of the invention on whichtransparent pixel electrodes appear;

[0027]FIG. 11 is a plan view of the structure of one surface of theelectrochromic display apparatus or electrodeposition type displayapparatus according to the sixth embodiment of the invention, on whichthe common electrode appears;

[0028]FIG. 12 is a circuit diagram of the electrochromic displayapparatus or electrodeposition type display apparatus according to thesixth embodiment of the invention; and

[0029]FIG. 13 is a graph of a result of measurement, which shows arelation between current density and optical density (color density) inan electrodeposition type display apparatus according to the invention.

BEST MODE FOR CARRYING OUT THE INVENTION

[0030] Electrochromic display apparatuses according to some embodimentsof the invention will now be explained below with reference to thedrawings. Any of the electrochromic display apparatuses according to theembodiments has a structure in which a plurality of electrochromicdisplay elements each having the structure of an electrochromic displaydevice are arranged in form of a sheet.

[0031] First Embodiment

[0032] As shown in FIGS. 1 and 2, the electrochromic display apparatusaccording to this embodiment is characterized in arranging a pluralityof electrochromic display devices in form of a sheet, eachelectrochromic display device including a transparent pixel electrode 12serving as a first transparent electrode controlled by TFT (Thin FilmTransistor) 13 as a drive device, a polymer layer 14 electrically activeand variable in color due to electrochemical oxidation or reduction, apolymeric solid electrolytic layer 15 in contact with the polymer layer14 and containing a coloring agent, and a common electrode 16 commonlyused by this and other pixels to function as a second electrode opposedto the first transparent electrode.

[0033] Each combination of the transparent pixel electrode 12 and TFT 13form one pixel, and a number of pixels are arranged in a matrix patternon a transparent support structure 11. As the transparent supportstructure 11, a transparent glass substrate such as quartz glass plateor whiteboard glass plate, for example, may be used. In addition tothese, other materials are also acceptable, namely, esters such aspolyethylene naphthalate and polyethylene terephthalate; celluloseesters such as polyamide, polycarbonate and cellulose acetate; fluorinepolymers such as polyvinylidene fluoride,polytetrafluoroethylene-cohexafluoropropylene; polyethers such aspolyoxymethylene; polyolefins such as polyacetal, polystyrene,polyethylene, polypropylene and metylpentene polymer; and polyimide suchas polyimide-amide and polyetherimide. In case of using any of thesesynthetic resins, it may be formed into a rigid substrate not bendingeasily, or may be formed into a flexible film-like structure.

[0034] The transparent pixel electrode 12 is made of a transparentconductive film formed in a substantially rectangular or square pattern,and as shown in FIG. 1, individual pixels are isolated. Locally therein,TFT 13 for each pixel is located. Here is preferably used an ITO film ofa mixture of In₂O₃ and SnO₂, or a film coated by SnO₂ or In₂O₃ It isalso acceptable to dope Sn or Sb into the ITO film or the SnO₂— orIn₂O₃-coated film, and MgO or ZnO are also usable.

[0035] TFT 13 formed in each pixel is selected by a wiring not shown tocontrol the associated transparent pixel electrode 12. TFT 13 is veryefficient for preventing cross-talk among pixels. TFT 13 is formed tooccupy a part of the transparent pixel electrode, for example.Alternatively, the transparent pixel electrode 12 may lie in a differentlevel from TFT 13 in the stacking direction. A gate line and a data lineare connected to TFT 13, its gate electrode is connected to each gateline, one of the source and the drain of TFT 13 is connected to a dataline, and the other of the source and the drain is electricallyconnected to the transparent pixel electrode 12. A drive device otherthan TFT 13 may be made of a different material if it can be formed on atransparent substrate in a matrix drive circuit used in a flat typedisplay.

[0036] The transparent pixel electrode 12 and TFT 13 are in contact witha polymer layer 14 that is a polymeric material layer. The polymer layer14 is made of a polymeric, electrochromic material that is electricallyactive. The polymer layer 14 is changed in color by electrochemicaloxidation or reduction, and when a potential difference is applied tothe transparent pixel electrode 12 as one of opposite electrodes of thecapacitance, it changes to black. The polymer layer 14 is preferablymade of a so-called conductive polymer obtained by electrolyticsynthesis. This is because the conductivity facilitates quick electronexchange interaction and ensures quick reaction of coloring anddecoloring. Examples of preferable polymers are shown in Table 1. Otherpolymer materials obtained by electrolytic oxidizing polymerization ofderivatives of pyrole, thiophene, azulene and aniline are also usable.It is also possible to use materials combining such materials with thepolymers shown in Table 1 and their derivatives. TABLE 1 OxidationReduction potential (vs. potential (vs. Coulomb Polymer Li⁺/Li) Li⁺/Li)efficiency Polypyrole 2.85 2.6 99% or more Polyaniline 4.2 4.0 99% ormore Polyazulene 3.6 3.2 99% or more Polythiophene 4.5 3.6 96%Polyindole 3.8 3.5 95% Polycarbazole 3.7 3.6 81%

[0037] One of especially preferable materials among polymer materialsshown in the table (polypyrole, polyaniline, polyazulene, polythiophene,polyindole and polycarbazole) is polypyrole. Its reasons are 1) lowoxidation potential, 2) high coulomb efficiency, 3) black coloring uponoxidation and 4) long repetition lifetime, among others. The reason whymaterials of low oxidation potentials are preferred lies in that thosematerials lower in oxidation potential are stable in a colored state.The reason why materials having high coulomb efficiency are considereddesirable lies in that the high coulomb efficiency demonstratessuppression of side reaction as much. When the coulomb efficiency isnearly 100%, it demonstrates that almost no side reaction occurs andresults in lower lifetime as a device. It is an important nature as adocument display that the coloring upon oxidation is black. Polypyroleis black upon complete oxidation while the other materials are green orreddish black. Therefore, by employing polypyrole, it is possible toenhance the black concentration and improve the contrast. Additionally,the long repetition lifetime is another useful nature of polypyrole.

[0038] A polymeric solid electrolytic layer 15 is formed in contact withthe coloring polymer 14. If the polymeric solid electrolyte forming thepolymeric solid electrolytic layer 15 and the polymer material as theelectrochromic material are compounded, it is advantageous to alleviatefalling or powdering of the polymer material from the electrode due tovolume changes caused by coloring and decoloring and thereby increasethe durability.

[0039] As the matrix polymer used in the polymeric solid electrolyteforming the polymeric solid electrolytic layer 15, examples of usablematerials are polyethylene oxide, polypropylene oxide, polyethyleneimine and polystyrene sulfide whose framework structure units areexpressed by —(C—C—O)_(n)—, —(C—C(CH₃)—O)_(n)—, —(C—C—N)_(n)— or—(C—C—S)_(n)—. Branches may be added to any of these materials formingthe main chain structure. Polymethylmethacrylate, polyvinylidenefluoride, polyvinylidene chloride and polycarbonate are also preferable.

[0040] When the polymeric solid electrolytic layer 15 is formed, aquantity of plasticizer is preferably added to the matrix polymer.Examples of preferable plasticizers are water, ethyl alcohol, isopropylalcohol and their mixture, for example when the matrix polymer ishydrophilic. If the matrix polymer is hydrophobic, propylene carbonate,dimethyl carbonate, ethylene carbonate, γ-butylolactone, acetonitrile,sulfolane, dimethoxyethane, ethyl alcohol, isopropyl alcohol,dimethylformamide, dimethylsulfoxide, dimethylacetamide,n-methylpyrolidone and their mixtures.

[0041] The polymeric solid electrolyte is formed by melting anelectrolytic substance into the matrix polymer, examples of usablematerials as the electrolyte are lithium salt such as LiCl, LiBr, LiI,LiBF₄, LiClO₄, LiPF₆ or LiCF₃SO₃, potassium salt such as KCl, KI or KBr,sodium salt such as NaCl, NaI, NaBr or tetra alkyl ammonium salt such astetra ethylene ammonium, boron tetra ethylene ammonium fluoride, tetraethylene ammonium perchlorate, boron tetrabuthylene ammonium fluoride,tetrabuthyl ammonium perchlorate or tetrabuthyl ammonium halide. Alkylchains of the above-mentioned 4-ammonium salt may be irregular.

[0042] If the polymeric solid electrolyte and the polymer material asthe electrochromic material are compounded, it is advantageous toalleviate falling or powdering of the polymer material from theelectrode due to volume changes caused by coloring and decoloring andthereby increase the durability. The polymeric solid electrolyte isobtained by first forming the polymeric solid electrolytic material onthe first electrode beforehand by an appropriate-method, and thereaftercarrying out electrolytic oxidizing polymerization in anelectrodeposition vessel containing pyrole monomer.

[0043] The polymeric solid electrolytic layer 15 contains a coloringagent for enhancing the contrast. In case the coloring of the polymerlayer 14 is black as mentioned above, a white material having a highconcealing property is used as the background color. As this kind ofmaterial, white coloring particles may be used, such as those oftitanium dioxide, calcium carbonate, silica, magnesium oxide, oraluminum oxide.

[0044] Mixture ratio of the coloring agent is preferably in the range ofapproximately 1 through 20 wt %, more preferably in the range ofapproximately 1 through 10 wt % and still more preferably in the rangeof approximately 5 to 10 wt % when inorganic particles are used.Inorganic white particles of titanium oxide, for example, do not solveinto polymers but merely disperse. Then, if the mixture ratio increases,inorganic particles aggregate, and it results in uneven optical density.Additionally, since those inorganic particles have no ion conductivity,an increase of the mixture ratio invites a decrease of the conductivityof the polymeric solid electrolyte. Taking both into consideration, theupper limit of the mixture ratio is approximately 20 wt %.

[0045] In case that inorganic particles are mixed as the coloring agent,thickness of the polymeric solid electrolytic layer 15 is adjustedpreferably in the range of 20 to 200 μm, more preferably in the range of50 to 150 μm and still more preferably in the range of 70 to 150 μm. Thepolymeric solid electrolytic layer 15 had better be thin because theresistance between electrodes decreases, and it contributes to adecrease of the coloring/decoloring time and power consumption. However,thinning the layer to 20 μm or less is not recommended because themechanical strength decreases to a level causing pin holes and cracking.In addition, if the layer is excessively thin, quantity of whiteparticles mixed inevitably decreases, and the white level (opticaldensity) is not sufficient.

[0046] The mixture ratio of the coloring agent may be 10 wt % when apigment is used because coloring efficiency of a pigment is much higherthan that of inorganic particles. Therefore, any electrochemicallystable pigment can make a contrast even when its quantity is small.Usually, an oil-soluble dye is preferable as the pigment.

[0047] On one side opposed to the first transparent electrode, a commonelectrode 16 is formed as the second electrode. The common electrode maybe made of any electrochemically stable material. Preferable materialsare platinum, chromium, aluminum, cobalt, palladium, and so on. Thecommon electrode can be made by forming a film of a conductor such as ametal film on a support structure 17. If a metal used for main reactioncan be supplied beforehand or any time thereafter, carbon can be used asthe common electrode. To support carbon on the electrode, there is themethod of preparing carbon ink by using a resin, and then print it onthe substrate surface. The use of carbon contributes to lowering thecost of the electrode.

[0048] The support structure 17 need not be transparent. It can be useda substrate or film which can reliably hold the common electrode 16 andthe polymeric solid electrolytic layer 15. Some examples are glassplates such as quartz glass plate and whiteboard glass plates, ceramicsubstrates, paper substrates and wood substrates. In addition to these,other materials are also usable as synthetic resin substrates, namely,esters such as polyethylene naphthalate and polyethylene terephthalate;cellulose esters such as polyamide, polycarbonate and cellulose acetate;fluorine polymers such as polyvinylidene fluoride,polytetrafluoroethylene-cohexafluoropropylene; polyethers such aspolyoxymethylene; polyolefins such as polyacetal, polystyrene,polyethylene, polypropylene and metylpentene polymer; and polyimide suchas polyimide-amide and polyetherimide. In case of using any of thesesynthetic resins, it may be formed into a rigid substrate not bendingeasily, or may be formed into a flexible film-like structure. If thecommon electrode 16 is sufficiently rigid, the support structure 17 maybe omitted.

[0049] As shown in FIG. 2, for the purpose of placing the firsttransparent electrode and the second electrode face-to-face, a sealingresin portion 18 is formed along the perimeter to hold both supportstructures 11, 17. The sealing resin portion 18 will reliably hold thesesupport structures 11, 17, and other intervening components, namely,transparent pixel electrode 12, TFT 13, polymer layer 14, polymericsolid electrolytic layer 15 and common electrode 16.

[0050] Using the above-explained structure, the electrochromic displayapparatus according to the embodiment is capable of matrix driving byusing TFT 13, and can enhance the contrast and the black optical densityby selecting an appropriate material of the polymer layer 14.

[0051] Second Embodiment

[0052] As shown in FIGS. 3 and 4, an electrodeposition type displayapparatus according to this embodiment is characterized in arranging aplurality of electrodeposition type display devices in form of a sheet,which each electrodeposition type display device includes a transparentpixel electrode 22 serving as the first transparent electrode controlledby TFT (Thin Film Transistor) 23 as a drive device; a polymeric solidelectrolytic layer 25 containing metal ions and a coloring agent, and acommon electrode 26 commonly used by this and other pixels to functionas the second electrode opposed to the first transparent electrode.

[0053] In the electrodeposition type display apparatus according to theembodiment, each combination of the transparent pixel electrode 22 andTFT 23 form one pixel, and a number of pixels are arranged in a matrixpattern on a transparent support structure 21. As the transparentsupport structure 11, a transparent glass substrate such as quartz glassplate or whiteboard glass plate, for example, may be used similarly tothe first embodiment. In addition to these, other materials are alsoacceptable, namely, esters such as polyethylene naphthalate andpolyethylene terephthalate; cellulose esters such as polyamide,polycarbonate and cellulose acetate; fluorine polymers such aspolyvinylidene fluoride, polytetrafluoroethylene-cohexafluoropropylene;polyethers such as polyoxymethylene; polyolefins such as polyacetal,polystyrene, polyethylene, polypropylene and metylpentene polymer; andpolyimide such as polyimide-amide and polyetherimide. In case of usingany of these synthetic resins, it may be formed into a rigid substratenot bending easily, or may be formed into a flexible film-likestructure.

[0054] The transparent pixel electrode 22 is made of a transparentconductive film formed in a substantially rectangular-or square pattern,and as shown in FIG. 3, individual pixels are isolated. Locally therein,TFT 23 for each pixel is located. Here is preferably used an ITO film ofa mixture of In₂O₃ and SnO₂, or a film coated by SnO₂ or In₂O₃ It isalso acceptable to dope Sn or Sb into the ITO film or the SnO₂— orIn₂O₃-coated film, and MgO or ZnO are also usable.

[0055] TFT 23 formed in each pixel is selected by a wiring not shown tocontrol the associated transparent pixel electrode 22. TFT 23 is veryefficient for preventing cross-talk among pixels. TFT 23 is formed tooccupy a part of the transparent pixel electrode, for example.Alternatively, the transparent pixel electrode 22 may lie in a differentlevel from TFT 23 in the stacking direction. A gate line and a data lineare connected to TFT 23, its gate electrode is connected to each gateline, one of the source and the drain of TFT 13 is connected to a dataline, and the other of the source and the drain is electricallyconnected to the transparent pixel electrode 22. A drive device otherthan TFT 23 may be made of a different material if it can be formed on atransparent substrate in a matrix drive circuit used in a flat typedisplay.

[0056] In the electrodeposition type display apparatus according to theinstant embodiment, the polymeric solid electrolytic layer 25 containsmetal ions used for changing the color. The metal ions used for colorchange electrochemically deposit as so-called electrolytic plating, andreciprocally elute as the opposite reaction to effectuate display. Metalions capable of coloring and decoloring by electrochemical depositionand elution are not limited to specific kinds of metals. However, someexamples of such metal ions are bismuth, copper, silver, lithium, iron,chromium, nickel and cadmium ions and their combinations. Especiallypreferable metal ions are bismuth and silver ions because reciprocalreaction can be easily brought about and the color changing degree upondeposition is high.

[0057] As the matrix polymer used in the polymeric solid electrolyteforming the polymeric solid electrolytic layer 25 containing metal ions,examples of usable materials are polyethylene oxide, polypropyleneoxide, polyethylene imine and polystyrene sulfide whose frameworkstructure units are expressed by —(C—C—O)_(n)—, —(C—C(CH₃)—O)_(n)—,—(C—C—N)_(n)— or —(C—C—S)_(n)—. Branches may be added to any of thesematerials forming the main chain structure. Polymethylmethacrylate,polyvinylidene fluoride, polyvinylidene chloride and polycarbonate arealso preferable.

[0058] When the polymeric solid electrolytic layer 25 is formed, aquantity of plasticizer is preferably added to the matrix polymer.Examples of preferable plasticizers are water, ethyl alcohol, isopropylalcohol and their mixture, for example when the matrix polymer ishydrophilic. If the matrix polymer is hydrophobic, propylene carbonate,dimethyl carbonate, ethylene carbonate, γ-butylolactone, acetonitrile,sulfolane, dimethoxyethane, ethyl alcohol, isopropyl alcohol,dimethylformamide, dimethylsulfoxide, dimethylacetamide,n-methylpyrolidone and their mixtures.

[0059] The polymeric solid electrolyte is formed by melting anelectrolytic substance into the matrix polymer, examples of usablematerials as the electrolyte are lithium salt such as LiCl, LiBr, LiI,LiBF₄, LiClO₄, LiPF₆ or LiCF₃SO₃, potassium salt such as KCl, KI or KBr,sodium salt such as NaCl, NaI, NaBr or tetra alkyl ammonium salt such astetra ethylene ammonium, boron tetra ethylene ammonium fluoride, tetraethylene ammonium perchlorate, boron tetrabuthylene ammonium fluoride,tetrabuthyl ammonium perchlorate or tetrabuthyl ammonium halide. Alkylchains of the above-mentioned 4-ammonium salt may be irregular.

[0060] The polymeric solid electrolytic layer 25 contains a coloringagent for enhancing the contrast. In case the coloring of the metal ionsis black as mentioned above, a white material having a high concealingproperty is used as the background color. As this kind of material,white coloring particles may be used, such as those of titanium dioxide,calcium carbonate, silica, magnesium oxide, or aluminum oxide. Further,a pigment for coloring can be used as well.

[0061] Mixture ratio of the coloring agent is preferably in the range ofapproximately 1 through 20 wt %, more preferably in the range ofapproximately 1 through 10 wt % and still more preferably in the rangeof approximately 5 to 10 wt % when inorganic particles are used. In casethat inorganic particles are mixed as the coloring agent, thickness ofthe polymeric solid electrolytic layer 25 is adjusted preferably in therange of 20 to 200 μm, more preferably in the range of 50 to 150 μm andstill more preferably in the range of 70 to 150 μm. Reasons of suchconditions are the same as those in the explanation of the fistembodiment. So explanation thereof is omitted here for avoidingredundancy.

[0062] The mixture ratio of the pigment-based coloring agent may be 10wt % because coloring efficiency of a pigment is much higher than thatof inorganic particles. Therefore, any electrochemically stable pigmentcan make a contrast even when its quantity is small. Usually, anoil-soluble dye is preferable as the pigment.

[0063] On one side opposed to the first transparent electrode, a commonelectrode 26 is formed as the second electrode. The common electrode maybe made of any electrochemically stable material. Preferable materialsare platinum, chromium, aluminum, cobalt, palladium, and so on. Thecommon electrode can be made by forming a film of a conductor such as ametal film on a support structure 27. If a metal used for main reactioncan be supplied beforehand or any time thereafter, carbon can be used asthe common electrode. To support o carry carbon on the electrode, thereis the method of preparing carbon ink by using a resin, and then printit on the substrate surface. The use of carbon contributes to loweringthe cost of the electrode.

[0064] The support structure 27 need not be transparent. It can be useda substrate or film which can reliably hold the common electrode 26 andthe polymeric solid electrolytic layer 25. Its candidate materials arethe same as those of support structure according to the firstembodiment. Additionally, as shown in FIG. 4, for the purpose of placingthe first transparent electrode and the second electrode face-to-face, asealing resin portion 28 is formed along the perimeter to hold bothsupport structures 11, 17. The sealing resin portion 28 will reliablyhold these support structures 21, 27, and other intervening components,namely, transparent pixel electrode 22, TFT 23, polymer layer 24,polymeric solid electrolytic layer 25 and common electrode 26.

[0065] Using the above-explained structure, the electrodeposition typedisplay apparatus according to the embodiment is capable of matrixdriving by using TFT 23, and can enhance the contrast and the blackoptical density by making use of metal ions contained in the polymericsolid electrolytic layer 25.

[0066] Third Embodiment

[0067] This embodiment is directed to a method of manufacturing theelectrochromic display apparatus according to the first embodiment. Themethod will be explained below in the order of its steps with referenceto FIGS. 5A through 5C and FIGS. 6A through 6C.

[0068] First referring to FIG. 5A, transparent pixel electrodes in formof an ITO film and thin-film transistors 33 are formed on a transparentsupport structure 31 such as a glass substrate for each pixel. Thethin-film transistor 33 is formed by using a known semiconductormanufacturing technique, and the ITO film is formed by a technique suchas vapor deposition or sputtering, for example. A transparent pixelelectrode 32 and a thin-film transistor 33 are formed for each pixel,and a number of pixels are arranged in an matrix array on thetransparent support structure 31.

[0069] After the transparent pixel electrodes 32 and the thin-filmtransistors 33 are formed on the transparent support structure 31, alead portion connectable to a drive circuit 34 is formed. Then theentirety is immersed into electrodeposition liquid 36 in anelectrodeposition vessel 35. The electrodeposition liquid 36 functionsto electrolytically deposit a polymer layer of polypyrole, for example.The drive circuit 34 supplies electricity to each transparent pixelelectrode 32 to electrolytically deposit the polymer layer, not shown,of polypyrole, for example, on each transparent pixel electrode 32. Inthis process, the transparent pixel electrodes 32 face to anelectrodeposition electrode 37 via the electrodeposition liquid 36.Subsequently, the entirety is again immersed into the electrodepositionliquid in the electrodeposition vessel not containing a color-changingpolymer material (in this case, pyrole) to once return the tops of thetransparent pixel electrodes to transparency by deionizing the polymerlayer. Thereafter, the transparent support structure 31 is removed fromthe electrodeposition liquid, washed with ethanol, and dried by vacuumdrying.

[0070] After that, as shown in FIG. 5C, a polymeric solid electrolyticlayer 38 is formed on the transparent support structure 31. First, asynthetic resin as the matrix polymer of the polymeric solidelectrolytic layer 38 and a material forming the electrolyte such aslithium salt, potassium salt, sodium salt, or tetra alkyl ammonium saltare mixed, and white particles are additionally dispersed as a coloringagent to prepare the material. This polymeric solid electrolyticmaterial is coated to form the polymeric solid electrolytic layer 38.

[0071] In parallel therewith, a common electrode 39 in form of apalladium film of an appropriate thickness is formed on the supportstructure 40 in form of a polyethylene terephthalate. The commonelectrode 39 on the support structure 40 is press-fit to the polymericsolid electrolytic layer 38 not yet cured as shown in FIG. 6A, and theyare bonded together as shown in FIG. 6B. After the bonding, a polymericsolid electrolytic layer gelled by vacuum drying is formed between thesupport structure 40 and the transparent support structure 31. Then, asshown in FIG. 6C, a seal member 41 is attached to the end of the bondingto complete the electrochromic display apparatus.

[0072] In this embodiment, since the electrically active polymer layeris deposited by immersion into the electrodeposition liquid 36 in theelectrodeposition vessel 35 and a supply of electricity, the polymerlayer is formed on the transparent electrodes to be compoundedtherewith. Therefore, the polymer layer is prevented from falling orother undesirable events, and can be formed concentrically on thetransparent pixel electrodes 32.

[0073] Fourth Embodiment

[0074] This embodiment is directed to another method of manufacturingthe electrochromic display apparatus according to the first embodiment,which is a modification from the third embodiment. This embodiment willbe explained below in order of its steps with reference to FIGS. 7Athrough 7C.

[0075] Similarly to the manufacturing method of the third embodiment,first referring to FIG. 7A, transparent pixel electrodes in form of anITO film and thin-film transistors 33 are formed on a transparentsupport structure 31 such as a glass substrate for each pixel. Thethin-film transistor 33 is formed by using a known semiconductormanufacturing technique, and the ITO film is formed by a technique suchas vapor deposition or sputtering, for example. A transparent pixelelectrode 32 and a thin-film transistor 33 are formed for each pixel,and a number of pixels are arranged in an matrix array on thetransparent support structure 31. A lead portion (not shown) connectableto the drive circuit in a later step is also formed.

[0076] After that, as shown in FIG. 7B, a polymeric solid electrolyticlayer 38 is formed on the transparent support structure 31. First, asynthetic resin as the matrix polymer of the polymeric solidelectrolytic layer 38 and a material forming the electrolyte such aslithium salt, potassium salt, sodium salt, or tetra alkyl ammonium saltare mixed, and white particles are additionally dispersed as a coloringagent to prepare the material. This polymeric solid electrolyticmaterial is coated to form the polymeric solid electrolytic layer 38. Atthis stage, the polymeric solid electrolytic layer 38 is dried andgelled.

[0077] After the polymeric solid electrolytic layer 38 on thetransparent support structure 31 is dried and gelled, the entirety isimmersed into electrodeposition liquid 36 in an electrodeposition vessel35 as shown in FIG. 7C. The electrodeposition liquid 36 functions toelectrolytically deposit a polymer layer of polypyrole, for example. Thedrive circuit 34 supplies electricity to each transparent pixelelectrode 32 to electrolytically deposit the polymer layer, not shown,of polypyrole, for example, on each transparent pixel electrode 32. Inthis process, the transparent pixel electrodes 32 face to anelectrodeposition electrode 37 via the electrodeposition liquid 36.Immediately after the electrodeposition, the support structure as thesecond electrode and the surface with the common electrode are bonded,and through the steps shown in FIGS. 6A through 6C, the elctrochromicdisplay apparatus is completed.

[0078] Fifth Embodiment

[0079] This embodiment is directed to a method of manufacturing theelectrodeposition type display apparatus according to the secondembodiment. The method will be explained below in the order of its stepswith reference to FIGS. 8A through 8C, FIGS. 9A and 9B.

[0080] First referring to FIG. 8A, transparent pixel electrodes in formof an ITO film and thin-film transistors 53 are formed on a transparentsupport structure 51 such as a glass substrate for each pixel. Thethin-film transistor 53 is formed by using a known semiconductormanufacturing technique, and the ITO film is formed by a technique suchas vapor deposition or sputtering, for example. A transparent pixelelectrode 52 and a thin-film transistor 53 are formed for each pixel,and a number of pixels are arranged in an matrix array on thetransparent support structure 51.

[0081] After the transparent pixel electrodes 52 and the thin-filmtransistors 53 are formed on the transparent support structure 51, apolymeric solid electrolytic layer 54 is formed on the transparentsupport structure 51 as shown in FIG. 8B. In the process of forming thepolymeric solid electrolytic layer 54, a synthetic resin as the matrixpolymer of the polymeric solid electrolytic layer 54, a material formingthe electrolyte such as lithium salt, potassium salt, sodium salt, ortetra alkyl ammonium salt, and a metal ion generating agent such asbismuth chloride are mixed altogether, and white particles areadditionally dispersed as a coloring agent to prepare the material. Thispolymeric solid electrolytic material is coated to form the polymericsolid electrolytic layer 54.

[0082] In parallel therewith, as shown in FIG. 8C, a common electrode 55in form of a palladium film of an appropriate thickness is formed on thesupport structure 56 in form of a polyethylene terephthalate. The commonelectrode 55 on the support structure 56 is press-fit to the polymericsolid electrolytic layer 54 not yet cured, and they are bonded togetheras shown in FIG. 9A. After the bonding, a polymeric solid electrolyticlayer gelled by vacuum drying is formed between the support structure 56and the transparent support structure 51. Then, as shown in FIG. 9B, aseal member 57 is attached to the end of the bonding to complete theelectrodeposition type display apparatus.

[0083] In this embodiment, metal ions are introduced together with theelectrolyte at the step of preparation of the polymeric solidelectrolytic layer 54. Therefore, the polymeric solid electrolytic layer54 and the color-variable material are combined in a relatively easyprocess, and the manufacturing process is simplified accordingly.

[0084] Sixth Embodiment

[0085] The electrochromic display apparatus or electrodeposition typedisplay apparatus according to the embodiment is an example in whichpotential detector electrodes 64, 65 are formed as third electrodesindependently from the first transparent electrode and the secondelectrode (common electrode). These potential detector electrodes 64, 65are placed as electrically insulated members on a common plane of thetransparent support structure together with the transparent pixelelectrodes or common electrode, and they are used for detecting thepotential of the transparent pixel electrodes or common electrode on thetransparent support structure.

[0086]FIG. 10 is a plan view of one surface on which the transparentpixel electrodes appear. On a transparent support structure 61, atransparent pixel electrode 63 and a TFT 62 as a drive device are formedfor each pixel, and a number of pixels are arranged in a matrix array.The potential detector electrode 64 for detecting the potential oftransparent pixel electrodes is formed in space among pixels to extendin a cross-like pattern, and its end portions (shown by black dots) aresilver or aluminum electrodes having a thickness around 1000 nm. Theline portions connecting the end portions are silver or aluminum linearwiring portions having a width around 1 μm. Since this potentialdetector electrode 64 is a electrically insulated member formed on acommon plane together with the transparent pixel electrodes 63, it canprecisely monitor the potential of the transparent pixel electrodes 63,and thereby precisely detect reaction occurring in the transparent pixelelectrodes 63. As the material of the potential detector electrode 64, astable metal material free from spontaneous elution into mediumsabsolutely irrelevant to reaction is preferably selected. For example,platinum, chromium, aluminum, cobalt, palladium or silver can beselected similarly to the second electrode.

[0087]FIG. 11 is a plan view of one surface on which the commonelectrode appears. A common electrode is formed on the support structure66, and a potential detector electrode 65 is also formed in a patternsimilar to the inverted π. Since this potential detector electrode 65 isa electrically insulated member formed on a common plane together withthe common electrode 67, it can precisely monitor the potential of thecommon electrode 67, and thereby precisely detect reaction occurring inthe common electrodes 67. As the material of the potential detectorelectrode 65, a stable metal material free from spontaneous elution intomediums absolutely irrelevant to reaction is preferably selected. Forexample, platinum, chromium, aluminum, cobalt, palladium or silver canbe selected similarly to the second electrode. Since the potentialdetector electrode 65 can be made of the same material as that of thecommon electrode on the common plane, it can be easily formed bypatterning the space-between the potential detector electrode 65 and thecommon electrode 67.

[0088]FIG. 12 is a circuit diagram of the electrochromic displayapparatus or electrodeposition type display apparatus having a potentialdetector electrode 76. A number of pixels each composed of TFT 74 and atransparent pixel electrode 75 are arranged in a matrix array, and oneof opposite electrodes of the capacitance serves as a common electrode.Data line drive circuits 72, 72a and a gate line drive circuit forselecting respective pixels are provided, and a predetermined data line78 and a gate line 77 are selected by a signal from a signal controller71. The potential detector electrode 76 is configured to connect fromthe signal controller 71, and the potential of the pixel portion can bemonitored with the supply of a signal from the potential detectorelectrode 76. That is, a stable metal material free from spontaneouselution into mediums absolutely irrelevant to reaction is selected asthe material of the potential detector electrode 76, and the electrode76 can precisely monitor the progress of main reaction of electrochromicor metal precipitation dissolution. At the time when sufficientdeposition or electrochemical reaction is confirmed through the monitorusing the potential detector electrode 76, further reaction can bestopped.

[0089] Some examples will be explained together with their manufacturingmethods. Although various effects of the invention are explained by wayof these examples, the invention is not limited to them.

EXAMPLE 1

[0090] (Fabrication of Display Electrode)

[0091] A two-dimensional arrangement of ITO films and TFT (thin filmtransistor) aligned by 150 μm pitch were formed on a 1.5 mm thick glasssubstrate sized 10×10 cm. After a lead portion to be connected to thedrive circuit from the substrate was formed by a known technique, andthe entirety was next set in an electrodeposition vessel (see FIG. 5B).The electrodeposition liquid was prepared by solving 1M of tetraethylammonium tetrafluoroborate and 0.1M of pyrole in propylene carbonate.After that, 0.2 μA current was supplied to respective pixels from thedrive circuit until the supplied electricity reached 20 μC. As a result,black polypyrole deposited on each ITO.

[0092] Subsequently, the glass substrate was set in theelectrodeposition vessel containing the electrodeposition liquidobtained by solving 1M of tetraethyl ammonium tetrafluoroborate inpropylene carbonate, voltage of each pixel electrode is adjusted to 1Vrelative to an Ag⁺/Ag reference electrode, and polypyrole having dopedupon electrolytic polymerization was deionized. Polypyrole was changedto yellowish transparency. Subsequently, after the substrate was takenout and washed with ethanol, it was dried by vacuum drying.

[0093] (Adjustment and Coating of Polymeric Solid Electrolyte)

[0094] 1 weight part of polyvinylidene fluoride of molecular weight350,000 approximately was mixed in 10 weight part of 1:1 mixture solventof propylene carbonate and ethylene carbonate containing 1.7 weight partof boron tetrabuthyl ammonium fluoride, and the mixture was heated to120° C. to prepare a homogenous solution. Subsequently, 0.2 weight partof titanium dioxide having the mean grain size 0.5 μm was added to thesolution, and uniformly dispersed by homogenizer. This was next coatedon the glass substrate with a doctor blade Up to the thickness 60 μm,then the common electrode as the second electrode, explained later, wasimmediately bonded, and dries by vacuum drying under 110° C. and 0.1 Mpafor one hour. Thus the gelled polymeric solid electrolyte was formedbetween two electrodes. The end surfaces with the bonding seam weresealed with an adhesive.

[0095] (Second Electrode (counter electrode, common Electrode))

[0096] A 3000 Å palladium film was formed on a 0.5 mm thick polyethyleneterephthalate film sized 10×10 cm by sputtering. It was press-fitimmediately after being coated with the polymeric solid electrolyte.

[0097] (Drive and Estimation of Display Characteristics)

[0098] Using a known active matrix drive circuit, display electrodeswere oxidized with 5 μC electricity per pixel upon coloring, and reducedwith the same quantity of electricity upon decoloring to switch theblack display and colorless (white) display. Reflectance of colorlessdisplay was 70%, and optical density (OD) of the display portion uponcoloring (black) was approximately 1.3 (reflectance 5%). Therefore,reflectance contrast of 1:12 was obtained. After the sample wasmaintained in the coloring state, the circuit was opened, and the samplewas left. After one week, optical density of the display portion wasapproximately 1.0, and the sample was confirmed to have a memorycapability. The cycle of coloring and decoloring was repeated, and thenumber of repetition cycles until the black concentration upon coloringdegrades to 1.0 or lower was approximately eight million times.

EXAMPLE 2

[0099] Polymeric solid electrolyte was coated on a TFT substratebeforehand and dried and gelled similarly to Example 1. Thereafter, thesubstrate was introduced into the electrodeposition vessel, andelectricity was supplied similarly to Example 1. As a result, polypyroledeposited on ITO electrodes in a compounded form with the matrix polymerof polymeric solid electrolyte. The substrate was removed from theelectrodeposition vessel and immediately bonded to the counter electrode(second electrode), and the sample was dried under the same condition.

[0100] When the sample was driven and evaluated similarly to Example 1,the repetition number of cycles was approximately thirty million times,and the other characteristics were equivalent.

EXAMPLE 3

[0101] (Fabrication of Display Electrodes, and Preparation and Coatingof Polymeric Solid Electrolyte)

[0102] A two-dimensional arrangement of ITO films and TFT (thin filmtransistor) aligned by 150 μm pitch were formed on a 1.5 mm thick glasssubstrate sized 10×10 cm. Thereafter, 1 weight part of polyvinylidenefluoride of molecular weight 350,000 approximately was mixed in 10weight part of 1:1 mixture solvent of water and isopropyl alcoholcontaining 1.7 weight part of lithium bromide and 1.7 weight part ofbismuth chloride, and the mixture was heated to 120° C. to prepare ahomogenous solution. Subsequently, 0.2 weight part of titanium dioxidehaving the mean grain size 0.5 μm was added to the solution, anduniformly dispersed by homogenizer. This was next coated on the glasssubstrate with a doctor blade up to the thickness 60 μm, then the commonelectrode as the second electrode, explained later, was immediatelybonded, and dries by vacuum drying under 110° C. and 0.1 Mpa for onehour. Thus the gelled polymeric solid electrolyte was formed between twoelectrodes. The end surfaces with the bonding seam were sealed with anadhesive.

[0103] (Second Electrode (counter electrode, common Electrode))

[0104] A 3000 Å palladium film was formed on a 0.5 mm thick polyethyleneterephthalate film sized 10×10 cm by sputtering. It was press-fitimmediately after being coated with the polymeric solid electrolyte.

[0105] (Drive and Estimation of Display Characteristics)

[0106] Using a known active matrix drive circuit, display electrodeswere oxidized with 5 μC electricity per pixel upon coloring, and reducedwith the same quantity of electricity upon decoloring to switch theblack display and colorless (white) display. Reflectance of colorlessdisplay was 70%, and optical density (OD) of the display portion uponcoloring (black) was approximately 0.8 (reflectance 13%). Therefore,reflectance contrast of 1:5 was obtained. After the sample wasmaintained in the coloring state, the circuit was opened, and the samplewas left. After one week, no substantial change in optical density ofthe display was observed, and the sample was confirmed to have a memorycapability. The cycle of coloring and decoloring was repeated, and thenumber of repetition cycles until the black concentration upon coloringdegrades to 1.0 or lower was approximately eighty million times.

EXAMPLE 4

[0107] A sample was prepared using the same conditions that of Example3, excepting the use of a mixture of polyvinylidene chloride fluoride,LiBF₄ and AgClO₄. When the sample was driven and evaluated similarly toExample 3, the repetition number of cycles was approximately thirtymillion times, and the other characteristics were equivalent.

EXAMPLE 5

[0108] Measurement was carried out in regard to relations between thequantity of electricity supplied to pixel electrodes in anelectrodeposition type display apparatus and coloring concentration(optical density) of the pixels by deposited silver. Results of themeasurement are shown in FIG. 13. To obtain well visible characters, ingeneral, concentration of the character portion should be at least 1.0in optical density (OD), and preferably at least 1.5. Therefore, it isappreciated from the results shown in FIG. 13 that the quantity ofelectricity required is approximately not less than 5 mC/cm², andpreferably not less than 10 mC/cm². Quantity of electricity below thatrange will produce pale characters difficult to read. Optical densitybeyond 1.5 will provide sufficient visibility. However, even if it israised than that value, visibility is not improved so much because ofsaturation for the human sense. Additionally, when optical density israised beyond 1.5, since a large quantity of metal such as silverdeposits, opposite reaction (decoloring reaction) will becomeinsufficient, and incomplete extinguishment will occur. Therefore,quantity of electricity supplied is preferably adjusted to or below 20mC/cm².

[0109] According to the above-explained structure, the electrochromicdisplay device and apparatus according to the invention are capable ofmatrix driving by using drive devices formed in respective pixels, andcan enhance the contrast and the black concentration by the use of apolymer material in contact with the polymeric solid electrolyte tocolor electrochemical oxidation and reduction.

[0110] The electrodeposition type display device and apparatus canremove the problem of bronzing and keep the black concentration higheven after long-use because of the use of polymeric solid electrolytecontaining metal ions.

[0111] The manufacturing method of an electrochromic display apparatusor an electrodeposition type display apparatus according to theinvention can easily manufacture the electrochromic display apparatus orelectrodeposition type display apparatus having the above-explainedstructure.

1. An electrochromic display device comprising: a first transparentelectrode controlled by a drive device: a polymer material layer locatedin contact with said transparent electrode and electrically active to bechangeable in color by electrochemical oxidation or reduction; apolymeric solid electrolytic layer located in contact with said polymermaterial layer and containing a coloring agent; and a second electrodelocated to interpose said polymer material layer and said polymericsolid electrolytic layer between said first transparent electrode andsaid second electrode.
 2. The electrochromic display device according toclaim 1 wherein the polymer material forming said polymer material layeris polypyrole, polyaniline, polythiophene, polyazulene, or a mixturethereof.
 3. The electrochromic display device according to claim 1wherein the polymer material forming said polymer material layer is apolymer obtained by electric oxidizing polymerization of pryrole,aniline, thiophene, azulene, or their derivatives.
 4. The electrochromicdisplay device according to claim 1 wherein the polymeric solidelectrolyte forming said polymeric solid electrolytic layer ispolyethylene oxide, polypropylene oxide, polyethylene imine orpolystyrene sulfide whose framework structure unit is expressed by—(C—C—O)_(n)—, —(C—C(CH₃)—O)_(n)—, —(C—C—N)_(n)— or —(C—C—S)_(n)—, or apolymer material including any of those materials as the main chainstructure thereof and having branches, or polymethylmethacrylate,polyvinylidene fluoride, polyvinylidene chloride, polycarbonate, or amixture or lamination thereof mixed with metallic salt, or alkylammonium salt.
 5. The electrochromic display device according to claim 1wherein said polymeric solid electrolytic layer is a lamination of aplurality of layers, and said coloring agent is contained only in one orsome of said layers.
 6. The electrochromic display device according toclaim 1 wherein a plasticizer selected from water, ethyl alcohol,isopropyl alcohol, propylene carbonate, dimethyl carbonate, ethylenecarbonate, γ-butylolactone, acetonitrile, sulfolane, dimethoxyethane,dimethylformamide, dimethylsulfoxide, or mixtures thereof, is added tosaid polymeric solid electrolytic layer.
 7. The electrochromic displaydevice according to claim 1 wherein said coloring agent is an inorganicpigment, an organic pigment or a coloring matter.
 8. The electrochromicdisplay device according to claim 1 wherein said inorganic pigment ispowder of titanium dioxide, calcium carbonate, magnesium oxide oraluminum oxide.
 9. The electrochromic display device according to claim1 wherein said first transparent electrode contains SnO₂, In₂O₃ or theirmixture as a major component thereof.
 10. The electrochromic displaydevice according to claim 1 wherein said second electrode is a metalthin film.
 11. The electrochromic display device according to claim 1further comprising a third electrode independent from said firsttransparent electrode and said second electrode.
 12. The electrochromicdisplay device according to claim 1 wherein said third electrode islocated as an electrically insulated element on a common plane togetherwith said first transparent electrode and said second electrode.
 13. Anelectrodeposition type display device comprising: a first transparentelectrode controlled by a drive device; a polymeric solid electrolyticlayer containing a coloring agent and metal ions; and a second electrodelocated to interpose said polymeric solid electrolytic layer betweensaid first transparent electrode and said second electrode.
 14. Theelectrodeposition type display device according to claim 13 wherein saidmetal ions are bismuth, copper, silver, lithium, iron, chromium, nickelor cadmium ions, or a combination thereof.
 15. The electrodepositiontype display device according to claim 13 wherein the polymeric solidelectrolyte forming said polymeric solid electrolytic layer ispolyethylene oxide, polypropylene oxide, polyethylene imine orpolystyrene sulfide whose framework structure unit is expressed by—(C—C—O)_(n)—, —(C—C(CH₃)—O)_(n)—, —(C—C—N)_(n)— or —(C—C—S)_(n)—, or apolymer material including any of those materials as the main chainstructure thereof and having branches, or polymethylmethacrylate,polyvinylidene fluoride, polyvinylidene chloride, polycarbonate, or amixture or lamination thereof mixed with metallic salt, or alkylammonium salt.
 16. The electrodeposition type display device accordingto claim 13 wherein said polymeric solid electrolytic layer is alamination of a plurality of layers, and said coloring agent iscontained only in one or some of said layers.
 17. The electrodepositiontype display device according to claim 13 wherein a plasticizer selectedfrom water, ethyl alcohol, isopropyl alcohol, propylene carbonate,dimethyl carbonate, ethylene carbonate, γ-butylolactone, acetonitrile,sulfolane, dimethoxyethane, dimethylformamide, dimethylsulfoxide, ormixtures thereof, is added to said polymeric solid electrolytic layer.18. The electrodeposition type display device according to claim 13wherein said coloring agent is an inorganic pigment, an organic pigmentor a coloring matter.
 19. The electrodeposition type display deviceaccording to claim 18 wherein said inorganic pigment is powder oftitanium dioxide, calcium carbonate, magnesium oxide or aluminum oxide.20. The electrodeposition type display device according to claim 13wherein said first transparent electrode contains SnO₂, In₂O₃ or theirmixture as a major component thereof.
 21. The electrodeposition typedisplay device according to claim 13 wherein said second electrode is ametal thin film.
 22. The electrodeposition type display device accordingto claim 13 wherein a material layer capable of introducing andreleasing ions or a material layer capable of producing anelectrochemical oxidation-reduction reaction is placed between saidpolymeric solid electrolytic layer and said second electrode.
 23. Theelectrodeposition type display device according to claim 22 wherein saidmaterial layer contains carbon.
 24. The electrodeposition type displaydevice according to claim 22 wherein said polymeric solid electrolyticlayer contains a growth inhibitor for inhibiting deposition of saidmetal ions.
 25. The electrodeposition type display device according toclaim 13 wherein said growth inhibitor has a group including an oxygenatom or a sulfur atom.
 26. The electrodeposition type display deviceaccording to claim 13 wherein said polymeric solid electrolytic layercontains a reducing agent or a oxidizer for suppressing side reactionwhich may occur in any of said first transparent electrode and saidsecond electrode when said metal ions deposit.
 27. The electrodepositiontype display device according to claim 13 wherein quantity ofelectricity supplied to between said electrodes is adjusted in the rangenot smaller than 5 mC and not larger than 20 mC per square centimeter.28. An electrochromic display apparatus comprising a sheet-like array ofa plurality of electrochromic display elements each including: a firsttransparent electrode controlled by a drive device: a polymer materiallayer located in contact with said transparent electrode andelectrically active to be changeable in color by electrochemicaloxidation or reduction; a polymeric solid electrolytic layer located incontact with said polymer material layer and containing a coloringagent; and a second electrode located to interpose said polymer materiallayer and said polymeric solid electrolytic layer between said firsttransparent electrode and said second electrode.
 29. Anelectrodeposition type display device comprising a sheet-like array of aplurality of electrodeposition type display elements each including: afirst transparent electrode controlled by a drive device; a polymericsolid electrolytic layer containing a coloring agent and metal ions; anda second electrode located to interpose said polymeric solidelectrolytic layer between said first transparent electrode and saidsecond electrode.
 30. A method of manufacturing an electrochromicdisplay apparatus comprising: the step of forming transparent pixelelectrodes and drive devices on a transparent support structure; thestep of forming a polymer material layer electrically active andchangeable in color by electrochemical oxidization or reduction, and apolymeric solid electrolytic layer containing a coloring agent on saidtransparent support structure having formed said transparent pixelelectrodes and said drive devices; and the step of forming a commonelectrode opposed to said transparent pixel electrodes.
 31. A method ofmanufacturing an electrodeposition type display apparatus comprising:the step of forming transparent pixel electrodes and drive devices on atransparent support structure; the step of forming a polymeric solidelectrolytic layer containing metal ions and a coloring agent on saidtransparent support structure having formed said transparent pixelelectrodes and said drive devices; and the step of forming a commonelectrode opposed to said transparent pixel electrodes.